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排序方式: 共有664条查询结果,搜索用时 46 毫秒
31.
Azizul Haque Arabinda Das Supriti Samantaray Denise Matzelle Mollie Capone Gerald Wallace Aarti N. Husarik Saied Taheri Russel J. Reiter Abhay Varma Swapan K. Ray Naren L. Banik 《International journal of molecular sciences》2022,23(4)
Spinal cord injury (SCI) causes significant mortality and morbidity. Currently, no FDA-approved pharmacotherapy is available for treating SCI. Previously, low doses of estrogen (17β-estradiol, E2) were shown to improve the post-injury outcome in a rat SCI model. However, the range of associated side effects makes advocating its therapeutic use difficult. Therefore, this study aimed at investigating the therapeutic efficacy of Premarin (PRM) in SCI. PRM is an FDA-approved E2 (10%) formulation, which is used for hormone replacement therapy with minimal risk of serious side effects. The effects of PRM on SCI were examined by magnetic resonance imaging, immunofluorescent staining, and western blot analysis in a rat model. SCI animals treated with vehicle alone, PRM, E2 receptor antagonist (ICI), or PRM + ICI were graded in a blinded way for locomotor function by using the Basso–Beattie–Bresnahan (BBB) locomotor scale. PRM treatment for 7 days decreased post-SCI lesion volume and attenuated neuronal cell death, inflammation, and axonal damage. PRM also altered the balance of pro- and anti-apoptotic proteins in favor of cell survival and improved angiogenesis and microvascular growth. Increased expression of estrogen receptors (ERs) ERα and ERβ following PRM treatment and their inhibition by ER inhibitor indicated that the neuroprotection associated with PRM treatment might be E2-receptor mediated. The attenuation of glial activation with decreased inflammation and cell death, and increased angiogenesis by PRM led to improved functional outcome as determined by the BBB locomotor scale. These results suggest that PRM treatment has significant therapeutic implications for the improvement of post-SCI outcome. 相似文献
32.
This paper describes a PC based centralized monitoring of the running condition of a multi-machine system. This kind of monitoring from remote central location is one of the primary requirements in today’s era of automation. The convergence of embedded system like microcontroller/DSP/FPGA, etc., now-a-days, is adding a new dimension to enhance the capability of the PC based data acquisition. In this present approach, conditions of different parameters of each motor have been measured by dedicated microcontroller based hardware. All these units are connected in a network using bus topology. All parameters are communicated to a remote PC through this bus where user friendly state-of-the-art developed software stores it for display and analysis purposes. 相似文献
33.
Peptide‐Based Fluorescent Probes for Deacetylase and Decrotonylase Activity: Toward a General Platform for Real‐Time Detection of Lysine Deacylation
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Dr. Debra R. Rooker Yuliya Klyubka Dr. Ritika Gautam Prof. Dr. Elisa Tomat Prof. Dr. Daniela Buccella 《Chembiochem : a European journal of chemical biology》2018,19(5):496-504
Histone deacetylases regulate the acetylation levels of numerous proteins and play key roles in physiological processes and disease states. In addition to acetyl groups, deacetylases can remove other acyl modifications on lysines, the roles and regulation of which are far less understood. A peptide‐based fluorescent probe for single‐reagent, real‐time detection of deacetylase activity that can be readily adapted for probing broader lysine deacylation, including decrotonylation, is reported. Following cleavage of the lysine modification, the probe undergoes rapid intramolecular imine formation that results in marked optical changes, thus enabling convenient detection of deacylase activity with good statistical Z′ factors for both absorption and fluorescence modalities. The peptide‐based design offers broader isozyme scope than that of small‐molecule analogues, and is suitable for probing both metal‐ and nicotinamide adenine dinucleotide (NAD+)‐dependent deacetylases. With an effective sirtuin activity assay in hand, it is demonstrated that iron chelation by Sirtinol, a commonly employed sirtuin inhibitor, results in an enhancement in the inhibitory activity of the compound that may affect its performance in vivo. 相似文献
34.
Somip Borphukan Maitrayee Saikia Urmilla Baruah Arvind Gautam Shashi D. Baruah Prakash J. Saikia 《应用聚合物科学杂志》2019,136(39):47994
The emulsion copolymerization of ethylene with butyl methacrylate (BMA) was carried out in an aqueous medium at 60 °C under moderate reaction conditions. The polymer system is well controlled with a linear increase in the molecular weight (Mn) versus ethylene feed pressure and narrow molecular weight distributions (>1.36) were observed throughout the copolymerization reaction. The spectroscopic analyses confirm the presence of acrylate functional as well as methylene group in the synthesized poly(ethylene-co-BMA) copolymer. Morphological behavior of poly(ethylene-co-BMA) has been studied using SEM and TEM analyses. Thermal stability of the copolymers was investigated by thermogravimetric analysis and it was observed that the copolymer is stable up to 380 °C. X-ray diffraction analysis confirmed the amorphous behavior of poly(ethylene-co-BMA). Dynamic light scattering measurement confirms the formation of poly(ethylene-co-BMA) nanoparticles. The particle size of copolymer nanoparticles were in the range of 85–108 nm with low polydispersity indexes (>0.2). The viscous and the elastic property of the copolymer were investigated and established that at high temperature elastic behavior predominant over viscous effect. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47994. 相似文献
35.
Energy yield simulations of interconnected solar PV arrays 总被引:4,自引:0,他引:4
In this paper, the electrical characteristics of array interconnection schemes are investigated using simulation models to find a configuration that is comparatively less susceptible to shadow problem and power degradation resulting from the aging of solar cells. Three configurations have been selected for comparison: (i) simple series-parallel (SP) array which has zero interconnection redundancy; (ii) total-cross-tied (TCT) array which is obtained from the simple SP array by connecting ties across each row of junctions; it may be characterized as the scheme with the highest possible redundancy; and (iii) bridge-linked (BL) array in which all cells are interconnected in bridge rectifier fashion. The explicit computer simulations for the energy yield and current-voltage distributions in the array are presented, which seem to favor cross-tied configurations (TCT and BL) in coping with the effects of mismatch losses. 相似文献
36.
The fate of [1-14C] linoleic acid and [1-14C] linolenic acid in the liver slices and also in the liver tissues of live carnivorous catfish,Heteropneustes fossilis andClarias batrachus, was studied. Incorporation of the fatty acids into different lipid classes in the live fish differed greatly from the tissue
slices, indicating certain physiological control operative in vivo. The extent of desaturation and chain elongation of linoleic
and linolenic acids into long-chain polyunsaturated fatty acids was low. Linolenic acid was oxidized (thus labeling the saturated
fatty acid with liberated14C-acetyl-CoA) in preference to linoleic acid, and this oxidation also seemed to be under physiological control since both
of the fatty acids were poorly oxidized in the tissue slices and in the killed fish. These fish can therefore recognize the
difference in the acyl chain structures of linoleate and linolenate. The higher oxidation of liolenic acid and poor capacity
for its conversion to longer chain, highly unsaturated derivatives indicates a higher demand for the dietary supply of these
essential fatty acids in these two species. 相似文献
37.
Photocatalytic degradation of 4-nitroaniline using solar and artificial UV radiation 总被引:2,自引:0,他引:2
Satyen Gautam Sanjay P. Kamble Sudhir B. Sawant Vishwas G. Pangarkar 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2005,110(1-3):129-137
The photocatalytic degradation (PCD) of 4-nitroaniline was studied in the presence of TiO2 suspensions in a batch and continuous annular reactor. Artificial and solar radiation was employed as sources of UV radiation. The effect of catalyst loading, pH, presence of anions and initial concentration on the rate of photocatalytic degradation was investigated. p-Aminophenol, p-benzoquinone and hydroquinone were identified as the intermediates during the degradation process. A kinetic expression for PCD of 4-NA is provided. 相似文献
38.
Comparative study of arsenic removal by iron using electrocoagulation and chemical coagulation 总被引:1,自引:0,他引:1
This research studied As(III) and As(V) removal during electrocoagulation (EC) in comparison with FeCl3 chemical coagulation (CC). The study also attempted to verify chlorine production and the reported oxidation of As(III) during EC. Results showed that As(V) removal during batch EC was erratic at pH 6.5 and the removal was higher-than-expected based on the generation of ferrous iron (Fe2+) during EC. As(V) removal by batch EC was equal to or better than CC at pH 7.5 and 8.5, however soluble Fe2+ was observed in the 0.2-μm membrane filtrate at pH 7.5 (10-45%), and is a cause for concern. Continuous steady-state operation of the EC unit confirmed the deleterious presence of soluble Fe2+ in the treated water. The higher-than-expected As(V) removals during batch mode were presumed due to As(V) adsorption onto the iron rod oxyhydroxides surfaces prior to the attainment of steady-state operation. As(V) removal increased with decreasing pH during both CC and EC, however EC at pH 6.5 was anomalous because of erratic Fe2+ oxidation. The best adsorption capacity was observed with CC at pH 6.5, while lower but similar adsorption capacities were observed at pH 7.5 and 8.5 with CC and EC. A comparison of As(III) adsorption showed better removals during EC compared with CC possibly due to a temporary pH increase during EC. In contrast to literature reports, As(III) oxidation was not observed during EC, and As(III) adsorption onto iron hydroxides during EC was only 5-30% that of As(V) adsorption. Also in contrast to literature, significant Cl2 was not generated during EC, in fact, the rods actually produced a significant chlorine demand due to reduced iron oxides on the rod. Although Cl2 generation and As(III) oxidation are possible using a graphite anode, a combination of graphite and iron rods in the same EC unit did not produce As(III) oxidation. However, a two-stage process (graphite anode followed by iron anode in separate chambers) was effective in As(III) oxidation and removal. The competing ions, silica and phosphate interfered with As(V) adsorption during both CC and EC. However, the degree of interference depends on the concentration and presence of other competing ions. In particular, the presence of silica lowered the effect of phosphate with increasing pH due to silica’s own significant effect at high pHs. 相似文献
39.
Seiko Jose Robin Das Izhar Mustafa Sujoy Karmakar Gautam Basu 《Journal of Natural Fibers》2019,16(4):536-544
The use of textile-grade fiber extracted from the Indian pineapple leaf is an unexplored area. Pineapple leaf fiber (PALF) is fine, soft, and moderately strong and is much acceptable for fashion garment. An attempt has been made to extract and soften Indian PALF from the pineapple leaves by decortication and subsequent water retting. Decorticated cum retted fiber has shown better physicomechanical and surface appearance properties than decorticated fiber. Fine yarn (38 tex) was spun in a suitable spinning system, and the property performance was found to be suitable to make eco-sustainable novelty fabric. Fabric was developed by using cotton as warp yarn and PALF-based yarn as weft in a handloom. The developed fabric shows very good physical and mechanical properties, desired for apparels. This inferred that Indian PALF may be successfully used to make eco-niche apparel quality fabric as well as novelty textiles. 相似文献
40.
Amit Kumar Gorai Simit Raval Ashok Kumar Patel Snehamoy Chatterjee Tarini Gautam 《国际煤炭科学技术学报(英文)》2021,8(4):737-755
Coal is heterogeneous in nature,and thus the characterization of coal is essential before its use for a specific purpose.Thus,the current study aims to develop ... 相似文献